Re: Vomiting metal

That's baking powder. Baking soda is only bicarbonate of soda.

I should mention that baking soda should not be taken, even in small amounts, if you have any history at all of kidney stones or kidney problems. The sodium will prompt the formation of calcium stones, the most common type of kidney stone.

In retrospect, I wouldn't actually recommend it for the original poster, but only bringing it up to get some feedback.